1. Technical Field
The present invention relates to a light source device having a pair of electrodes and main and sub reflection mirrors, and further relates to a projector including this light source device.
2. Related Art
A certain type of light source lamp included in a projector has an auxiliary mirror capable of utilizing light from a light emitting tube as effectively as possible. According to this type of light source lamp, the temperature of an auxiliary mirror side electrode as one of two electrodes included in the light emitting tube increases in some cases due to adoption of a sub reflection mirror such as the auxiliary mirror. Thus, a technology of increasing the heat capacity of the auxiliary mirror side electrode for the purpose of temperature control has been proposed in WO2004/086453.
According to the light source lamp of the type described above, a part of light reflected by the sub reflection mirror reaches the main mirror side electrode as the other one of the two electrodes disposed on the side opposite to the auxiliary mirror. As a result, the temperature of the main mirror side electrode rapidly increases at the time of start-up of the light source lamp, and the tip of the electrode melts. This causes deterioration of the characteristics of the light source lamp in some cases.
It is possible to prevent rapid increase in the electrode temperature at the start of the light source lamp by decreasing lamp current increase at the start-up. In this case, however, a longer time is required for reaching the rated stable operation of the lamp.